Developing Guidelines for Precoating of Aggregates Used in Seal Coats [Report]

Details

• Creators:
  Lopez, Erica ; Rung, Michael ; Adwani, Dheeraj ; Masad, Ahmad ; Hazlett, Darren ; Bhasin, Amit
• Corporate Creators:
  University of Texas at Austin. Center for Transportation Research
• Corporate Contributors:
  Texas Department of Transportation. Research and Technology Implementation Office ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Binder Content Binder Precoat Guidelines Sweep Test Image Analysis Precoated Aggregates Seal Coating Surface Area Surfaces Vialit Test
• Publication/ Report Number:
  FHWA/TX-22/0-7057-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Texas;United States
• Edition:
  December 2019 – August 2022
• Corporate Publisher:
  University of Texas at Austin. Center for Transportation Research
• Abstract:
  Seal coats in Texas are unique because most binder is hot applied, and aggregates are precoated. Precoating eliminates dust and improves adhesion between aggregate and binder. There currently exists no guidelines or specifications in place that can allow engineers to specify and accept the quality and extent of binder used to precoat aggregates. Precoating with certain binders can result in poor adhesion and premature failure of the seal coats. Inadequate precoating can result in dusty aggregate that impedes aggregate adhesion. The objective of this study was to determine the amount of precoating that is optimal for seal coat aggregates. To address this objective, this study had three goals: • Examine different factors of precoated aggregates that influence seal coat performance. • Establish test methods and procedures to evaluate precoated aggregate adequacy. • Establish requirements and acceptance criteria of precoating to ensure adequacy of the precoating. The study used modifications of a sweep test and Vialit test for measuring seal coat aggregate adhesion and developed an image processing procedure to determine the percent area coverage of precoated seal coat aggregate. A laboratory testing program and field section evaluation were used to develop tentative limits for the percent of asphalt coverage for precoating and guidelines for implementation.
• Format:
  PDF
• Funding:
  0-7057
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:25b1667585682711a45bf29b688d2b07f59dc1062004ef3894987d4fdb51acd4c89423a53d0b09f0ef84d5353d378d8d6b9adf8af447465493ba3089f590281f
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/64699/dot_64699_DS1.pdf
• File Type:
  [PDF - 23.36 MB ]